Which of the following is the correct structure of $L$-alanine?

Assertion : Carboxypeptidase is an exopeptidase.
Reason : It cleaves the $N$-terminal bond.

The monomer of a polypeptide is........

The amino acid which is not optically active is

Which of the following statements are correct?
$A$) $\alpha$-amino acids present in proteins are $L$-amino acids.
$B$) Amino acids contain both $-NH_2$ and $-COOH$ groups.
$C$) The number of amino groups and carboxylic groups is always the same in amino acids.
$D$) Tyrosine was first obtained from cheese.
Choose the correct alternatives from below:

Which of the following acids behaves like a salt in aqueous solution?